1. Field of the Invention
The present invention relates to the field of catheters employed in the observation, diagnosis and treatment of vessels, body cavities and the like. More particularly, the present invention relates to a catheter combination that can position a medical instrument such as an endoscope quickly and easily inside body cavities and vessels, and especially small vessels such as cardiac arteries, and locate, evaluate and treat conditions in such areas.
2. Related Art
Catheter assemblies have been used, for example, to view and clear obstructions from various vessels such as cardiac arteries and the like. Such vessels may have become occluded by deposits and need to be explored for possible treatment, such as by angioplasty. The occlusion must first be located, preferably as quickly and easily as possible to minimize any possible trauma or complications as a result of the procedure. Once located, the operator can apply lasers, angioplasty or other methods to treat the occluded vessel.
In the past, treating physicians may have used multiple lumen catheters that accepted medical instruments, such as lasers, angioscopes and guide wires to get inside a vessel or artery to remove the occlusion. Hussein et al., U.S. Pat. No. 4,773,413, shows such a device. One of the problems with multiple lumen catheters is that they are relatively bulky and stiff, which sometimes causes vessel damage. Another problem is that these bulky, stiff catheters sometimes have difficultly passing through the tortuous passages of the vessels.
A steerable guide wire may be used to guide a catheter along a vessel to an obstruction within the vessel. Such an arrangement is shown in Wells, U.S. Pat. No. 4,844,062. The catheter includes two lumens, wherein an optical fiber is housed in one lumen of the catheter and the guide wire is housed in a second lumen of the catheter parallel to the first lumen to reduce perforations to the vessel wall.
Multi-lumen catheters and internally disposed guide wires result in bulky and often stiff catheter tubes which are difficult to manipulate and which are often able to access only relatively larger vessels. There is a need for a catheter and endoscope combination which allows the endoscope to access and traverse relatively small diameter body cavities and vessels. There is also a need for a catheter endoscope combination wherein the endoscope is moveable independently of the catheter while still maintaining the catheter position stable. There is also a need for a catheter endoscope combination wherein the endoscope is moveable relative to the catheter and allows infusion of solutions through the catheter even while the endoscope is in place. Additionally, there is a need for a catheter endoscope combination which uses a guide wire to locate the vessel under consideration and guide the endoscope to the desired location in the vessel, while still allowing the endoscope to be removed and substituted with another instrument.
Accordingly, it is an object of the present invention to provide a catheter and endoscope combination wherein the endoscope is axially moveable relative to the catheter while still maintaining the proper position of the catheter.
It is another object of the present invention to provide a catheter combination having a guide wire which allows removal of the catheter, and re-engagement or replacement of instruments while leaving the guide wire in place to preserve an easily negotiated path along the vessel.
It is an additional object of the present invention to provide a catheter combination offering an extremely low profile and small shaft size to facilitate maneuverability and placement of the catheter, even in tortuous passageways of the vessels.
It is a further object of the present invention to provide a catheter combination with a guide wire that does not need an internal guide wire lumen through the entire length of the catheter. The guide wire in a preferred form of the invention passes external to the main portion of the catheter, eliminating any need for a separate full length guide wire lumen.
It is another object of the present invention to provide an instrument with a guide wire tip having an aperture which will extend past the catheter tip and accept the guide wire at the aperture. The guide wire tip also has a unique outer configuration to minimize any possible trauma to a vessel during its travel in the vessel.
It is yet a further object of the present invention to provide a catheter endoscope combination which allows infusion of solutions through the catheter lumen and around the endoscope bundle.
It is yet another object of the present invention to provide an occlusion cuff catheter combination having one or more of the above-described features. It is a specific object of one form of the present invention to provide an occlusion cuff catheter combination wherein a guide wire extends external to almost the entire length of the catheter but passing internal to a portion of the occlusion cuff. It is a further object to provide an occlusion cuff catheter capable of achieving an effective seal in a vessel and retaining the capability of wire guided access.
It is yet another object of the present invention to provide an improved procedure utilizing a highly maneuverable, low profile, occlusion cuff catheter that uses a guide wire external to the main portion of the catheter along with a instrument that extends past the catheter lumen.